First observation of Λ_b⁰ → ΛK⁺π^- and Λ_b⁰ → ΛK⁺K^- decays at LHCb

2016/05/23 by Daniel O'Hanlon, O'Hanlon, Daniel
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions

paper · pdf · doi:10.48550/arxiv.1605.06990

openalex publication_date 2016/05/23 · openalex created_date 2024/04/11 · openalex updated_date 2026/07/28

Abstract

The physics potential for b-baryon decays has been relatively unexplored until the advent of the LHC, and as such important questions still exist about their fundamental properties, such as whether their decays exhibit C P violation. Presented here are observations of the decays Λ_b⁰ → ΛK⁺π^- and Λ_b⁰ → ΛK⁺K^-, made at a significance level of 8.1 and 15.8 Gaussian standard deviations, respectively, and measurements of their branching fractions. The phase-space integrated C P asymmetries of these decays are also measured and found to be consistent with zero. Limits are set on the branching fractions of other Λ_b⁰ and Ξ_b⁰ decays to Λh⁺h^{′ -} (where h is a kaon or pion).

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